Gas Kiln Troubleshooting

Sometimes things don't run smoothly as you would like them to. You'll run into problems with your Gas Kiln and need a quick fix. Try it at home, here are some troubleshooting tips to help get your kiln back up running again. Remember, even after troubleshooting your kiln, you might need additional help. Reach out to us or the great folks at Olympic and we can help. Here's the Tech line for Olympic 770-967-4009.


Pilot Bar or Ring will not light.

  1. Ignition system lights but the burners aren’t lighting the gas pressure is too high. Kilns firing on propane require 11-inches water column pressure and natural gas fired kilns run on 7-inches water column pressure.
  2. If the ignition system will not light then there’s not any gas coming to it. Check to see if the gas is turned on.
  3. If the ignition system lights but won’t stay lit, the thermocouple is not in the correct position. If the thermocouple is in the correct position, then the baso gas valve needs replacing.

Kiln is not reaching temperature.

Failure to reach temperature is either too much or too little gas. Too much gas is identified by excessive flame discharge. Too little gas is probably from a small gas line. Your kiln should have a gas regulator of 11 inches water column for propane and 7 inches water column for natural gas with a ¾” inside diameter pipe for updraft gas kilns and 1” inside diameter pipe for DownDraft gas kilns between the kiln and regulator. Have the air adjustments wide open for propane.

Kiln shuts off when gas valve turned too high.

Gas pressure is too high. Check the low pressure regulator at your gas source and have gas pressure at 7” water column for natural gas or 11” water column for propane. Another source to check is the holes in the ignition system. Enlarge the holes on the pilot to 3/32” below the thermocouple tip.

Bottom section of kiln is hotter than the top section of kiln.

Several reasons may be the cause of the bottom section firing hotter than the top section.

  1. Excessive back pressure is occurring because the top port cover is closed too much. Open top port.
  2. Gas is burning inside the horizontal air mixer tube. A good test to see if the gas is burning in the horizontal air mixer is to insert a broom straw about half way into the tube from the primary air opening. If the straw comes out burned, the gas mixture is burning inside the air mixer. This condition is not dangerous but it will make it nearly impossible for the kiln to reach high temperatures. Turn the gas off and slightly increase the amount of primary air in the opening. Re-ignite the kiln and begin firing again.
  3. Top shelf is too close to top port.
  4. Shelves are not spaced 1-inch apart.

Kiln does not get hot fast enough.

  1. Primary air plate is not opened enough. Increase primary air plate opening.
  2. The gas pressure in the kiln is insufficient. UpDraft gas kilns need a low pressure regulator with natural gas running on 7-inches water column pressure and propane running on a 11-inches water column pressure. DownDraft gas kilns come equipped with a low pressure regulator.
  3. Gas is burning inside the horizontal air mixer tube. See number 2 above.
  4. Over reduction will cause the temperature to drop considerably.
  5. The orifice size is too small for the gas pressure being used. See kiln specifications on pages 10 and 22.